You asked: Is there any significant difference between importing into DataTables and creating Workbook objects?
For things such as storing and retrieving data into cells of sheets, I prefer to use DataTable(). To do more advanced things such as finding out the color of a cell, I use
Set xlsApp = CreateObject("Excel.Application")
Set xlsWorkbook = xlsApp.Workbooks.Open("c:\tests.xls")
Also If I want to have more than one Workbook open at a time, I use the "Excel.Application Object.